This study is of particular interest because of the high activity of paclitaxel and doxorubicin as a drug combination in breast cancers. These two agents also have significant activity against ovarian and lung cancers. In this Phase I study, we are assessing the effect of PSC 833 on the pharmacokinetics and pharmacodynamics of doxorubicin in combination with paclitaxel, with the goal of defining: a) a maximally tolerated dose (MTD) of doxorubicin with paclitaxel by sequential, brief infusion; b) maximally tolerated doses for doxorubicin and paclitaxel when used in conjunction with PSC 833; and c) the maximally tolerated doses of doxorubicin and paclitaxel, when combined with PSC, utilizing G-CSF support. Patients initially receive doxorubicin and paclitaxel and are being enrolled in cohorts of three to ten patients per cohort. The MTD of these two agents will be determined. Detailed pharmacokinetics for doxorubicin, doxorubicinol, and paclitaxel will be performed. Patients return three weeks later to receive attentuated doses of doxorubicin, and paclitaxel with PSC 833, and pharmacokinetics will again be performed. Based on our experience with doxorubicin/Cyclosporine A, paclitaxel/PSC 833 and etoposide/PSC-833, we anticipate that PSC 833 will significantly increase the area under the curve (AUC) and the half-life of both doxorubicin and paclitaxel. Therefore, the initial doses of doxorubicin and paclitaxel when combined with PSC are less than 50% of the doses given to the patient without PSC 833. Patients will continue on the combination of doxorubicin, paclitaxel, and PSC 833 at three week intervals as tolerated, and doses will be escalated as nadir blood counts permit, with the intent of determining the MTD of these three agents in combination. Finally, if the maximally tolerated dose of doxorubicin, placlitaxel, and PSC 833 is determined by neutropenia, we will then establish the MTD of these drugs with G-CSF support.